International travelers who want an iPhone 4S for its global roaming should buy their handset from Sprint or Verizon Wireless. These two carriers will unlock your phone so you can use it with any international rate plan. (Updated below)

In order to use the iPhone 4 on T-Mobile you have to jailbreak it, unlock it and then annoyingly cut your fatty SIM into a Micro SIM. Annoying! T-Mobile is making it a little easier by giving Micro SIMs to their customers.

Most GSM phones use regular SIM cards. Which are small. The iPhone 4, iPad and uh, not many other devices use next-gen micro SIM cards. Which are smaller. Apple's just proposed a new SIM standard. Which is smallerer.

MAXroam's iPad-friendly microSIM will let you take your coffee-shop wankery from Starbucks to streetside cafes in Milan. Their microSIMs cost an extravagant €75/$95 for 50MB of data, but at least you'll be able to tweet smugly from your iPad, right?

Have a SIM card that, for some reason (the iPad), you'd like to chop down to MicroSIM form? It's possible, just follow this handy tutorial. (You pretty much just cut the casing very carefully, keeping contacts intact.) [JohnBenson via DVICE]

The iPad 3G may require a micro SIM—a lilliputian SIM card incompatible with anything else you own—but AT&T will be selling each bundled with a full SIM card adapter—meaning you could potentially use your data plan elsewhere. UPDATE: